Mailman 3 August 2017 - docs

[issue15339] document the threading "facts of life" in Python
by Chris Jerdonek Oct. 26, 2020

Oct. 26, 2020

New submission from Chris Jerdonek <chris.jerdonek(a)gmail.com>: I think it would be helpful if the Python documentation included certain high-level information about multi-threading in Python. At minimum, I think it would help for the documentation to provide a definition that can be linked to of what it means when some part of the Python documentation says something is "thread-safe". In particular, such a definition could clarify that this is different from being atomic. This might best be addressed by an entry in the glossary for the term "thread-safe". Other documentation possibilities include stating what guarantees one should or should not expect regarding thread-safety, both within and across implementations, and providing centralized guidance on how to approach multi-threaded programming in Python. A HOWTO is one possibility for addressing these other possibilities. This issue stems from the discussion in issue 15329, which is more specific. ---------- assignee: docs@python components: Documentation messages: 165336 nosy: cjerdonek, docs@python priority: normal severity: normal status: open title: document the threading "facts of life" in Python _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue15339> _______________________________________

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[issue12832] The documentation for the print function should explain/point to how to control the sys.stdout encoding
by R. David Murray Oct. 25, 2020

Oct. 25, 2020

New submission from R. David Murray <rdmurray(a)bitdance.com>: A common problem encountered when using python3 is writing non-ascii to stdout. This will work fine if stdout is a terminal and the terminal encoding handles the characters, but will fail if stdout is later redirected to a pipe. The docs for sys.stdout and for print should contain or point to an explanation of why, and how to solve the problem (ie: how to set the encoding for sys.stdout/sys.stderr). Note that IMO it makes more sense for sys.stdout to default to the LOCALE encoding, but that should be a separate issue. ---------- assignee: docs@python components: Documentation messages: 142880 nosy: docs@python, r.david.murray priority: normal severity: normal status: open title: The documentation for the print function should explain/point to how to control the sys.stdout encoding versions: Python 2.7, Python 3.2, Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue12832> _______________________________________

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[issue29981] Update Index set, dict, and generator 'comprehensions'
by Terry J. Reedy Oct. 25, 2020

Oct. 25, 2020

New submission from Terry J. Reedy: The index currently has comprehensions *list* with *list* linked to 6.2.5 List displays. I suggest: 1. Link *comprehensions* to 6.2.4. Displays for lists, sets and dictionaries 2. Add subentries *set*, *dict*, and *generator* linked to 2a. 6.2.6. Set displays 2b. 6.2.7. Dictionary displays 2c. 6.2.8. Generator expressions We don't *call* generator expressions 'generator comprehensions', but that is what they are syntactically and one looking for 'comprehensions' should be able to find them there. There is already *list* ... *comprehensions* ... *list comprehensions* with 'list' and 'list comprehensions' linked to glossary entries, while 'list, comprehensions' links to the same section as 'comprehensions, list'. 3. Add 'set/dictionary, comprehensions' sub-entries linked like 'list, com 4. Add Glossary entries and links like 'list comprehensions' ---------- assignee: docs@python components: Documentation keywords: easy messages: 291129 nosy: docs@python, terry.reedy priority: normal severity: normal stage: needs patch status: open title: Update Index set, dict, and generator 'comprehensions' type: behavior versions: Python 3.6, Python 3.7 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue29981> _______________________________________

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[issue25509] PyImport_ImportModule inaccurately described
by Memeplex Oct. 23, 2020

Oct. 23, 2020

New submission from Memeplex: The documentation (for 3.5) states that "[PyImport_ImportModule] is a simplified interface to PyImport_ImportModuleEx()" but the current implementation calls PyImport_Import instead, which is a higher level interface that takes into account import hooks. Older versions of PyImport_ImportModule (say 2.0) did call PyImport_ImportModuleEx, but that's no longer the case. The PyImport_Import* naming convention got a bit messy with the years and maybe I'm not understanding the intention quite well, but it seems to me that the documentation is outdated and that there is a change in semantics for PyImport_ImportModule. ---------- assignee: docs@python components: Documentation messages: 253674 nosy: docs@python, memeplex priority: normal severity: normal status: open title: PyImport_ImportModule inaccurately described versions: Python 3.5 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue25509> _______________________________________

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[issue12174] Multiprocessing logging levels unclear
by JJeffries Oct. 22, 2020

Oct. 22, 2020

New submission from JJeffries <jamesjeffries1(a)gmail.com>: It is unclear without reference to the logging module where the multiprocessing logging levels fit in the normal logging provided by the logging module, even though it says above the table "The table below illustrates where theses fit in the normal level hierarchy. +----------------+----------------+ | Level | Numeric value | +================+================+ | ``SUBWARNING`` | 25 | +----------------+----------------+ | ``SUBDEBUG`` | 5 | +----------------+----------------+" I propose adding further values from the logging module for clarification. ---------- assignee: docs@python components: Documentation messages: 136839 nosy: JJeffries, docs@python priority: normal severity: normal status: open title: Multiprocessing logging levels unclear versions: Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue12174> _______________________________________

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[issue13047] imp.find_module("") and imp.find_module(".")
by Arfrever Frehtes Taifersar Arahesis Oct. 22, 2020

Oct. 22, 2020

New submission from Arfrever Frehtes Taifersar Arahesis <Arfrever.FTA(a)GMail.Com>: It's undocumented that imp.find_module("") and imp.find_module(".") try to find __init__.py. There is also a small difference in behavior between them. sys.path by default contains "" as the first element, which is sufficient for imp.find_module("."), but not for imp.find_module(""): $ mkdir /tmp/imp_tests $ cd /tmp/imp_tests $ touch __init__.py $ python3.3 -c 'import imp, sys; print(repr(sys.path[0])); print(imp.find_module("."))' '' (None, '.', ('', '', 5)) $ python3.3 -c 'import imp, sys; print(repr(sys.path[0])); print(imp.find_module(""))' '' Traceback (most recent call last): File "<string>", line 1, in <module> ImportError: No module named '' If sys.path contains path (e.g. "." or absolute path) to directory with __init__.py file, then imp.find_module("") will succeed: $ PYTHONPATH="." python3.3 -c 'import imp, sys; print(repr(sys.path[0:2])); print(imp.find_module("."))' ['', '/tmp/imp_tests'] (None, '.', ('', '', 5)) $ PYTHONPATH="." python3.3 -c 'import imp, sys; print(repr(sys.path[0:2])); print(imp.find_module(""))' ['', '/tmp/imp_tests'] (None, '/tmp/imp_tests/', ('', '', 5)) $ python3.3 -c 'import imp, sys; sys.path.insert(1, "."); print(repr(sys.path[0:2])); print(imp.find_module("."))' ['', '.'] (None, '.', ('', '', 5)) $ python3.3 -c 'import imp, sys; sys.path.insert(1, "."); print(repr(sys.path[0:2])); print(imp.find_module(""))' ['', '.'] (None, './', ('', '', 5)) I think that imp.find_module(".") and imp.find_module("") should have the same behavior, and this behavior should be documented. ---------- assignee: docs@python components: Documentation, Interpreter Core messages: 144531 nosy: Arfrever, docs@python priority: normal severity: normal status: open title: imp.find_module("") and imp.find_module(".") versions: Python 2.7, Python 3.2, Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue13047> _______________________________________

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[issue14979] pdb: Link to source
by anatoly techtonik Oct. 22, 2020

Oct. 22, 2020

New submission from anatoly techtonik <techtonik(a)gmail.com>: http://docs.python.org/library/pdb.html#pdb.Pdb Documentation for pdb says: "The debugger is extensible — it is actually defined as the class Pdb. This is currently undocumented but easily understood by reading the source." There should a link to the source. ---------- assignee: docs@python components: Documentation, Library (Lib) messages: 162074 nosy: docs@python, techtonik priority: normal severity: normal status: open title: pdb: Link to source _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue14979> _______________________________________

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[issue19438] Where is NoneType in Python 3?
by mpb Oct. 21, 2020

Oct. 21, 2020

New submission from mpb: types.NoneType seems to have disappeared in Python 3. This is probably intentional, but I cannot figure out how to test if a variable is of type NoneType in Python 3. Specifically, I want to write: assert type (v) in ( bytes, types.NoneType ) Yes, I could write: assert v is None or type (v) is bytes But the first assert statement is easier to read (IMO). Here are links to various Python 3 documentation about None: [1] http://docs.python.org/3/library/stdtypes.html#index-2 [2] http://docs.python.org/3/library/constants.html#None Link [2] says: "None The sole value of the type NoneType." However, NoneType is not listed in the Python 3 documentation index. (As compared with the Python 2 index, where NoneType is listed.) [3] http://docs.python.org/3/library/types.html If NoneType is gone in Python 3, mention of NoneType should probably be removed from link [2]. If NoneType is present in Python 3, the docs (presumably at least one of the above links, and hopefully also the index) should tell me how to use it. Here is another link: [4] http://docs.python.org/3/library/stdtypes.html#bltin-type-objects "The standard module types defines names for all standard built-in types." (Except <class 'NoneType'> ???) None is a built-in constant. It has a type. If None's type is not considered to be a "standard built-in type", then IMO this is surprising(!!) and should be documented somewhere (for example, at link [4], and possibly elsewhere as well.) Thanks! ---------- assignee: docs@python components: Documentation messages: 201666 nosy: docs@python, mpb priority: normal severity: normal status: open title: Where is NoneType in Python 3? versions: Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue19438> _______________________________________

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[issue30612] Unusual Windows registry path syntax
by Christian Ullrich Oct. 20, 2020

Oct. 20, 2020

New submission from Christian Ullrich: In 3.6.1, the manual, section 3.1.3, has this to say: "Your administrator will need to activate the “Enable Win32 long paths” group policy, or set the registry value HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem@LongPathsEnabled to 1." Separating a value name from the key path with an @-sign, which is what the above is doing, is something I have never before seen anywhere. I suggest changing it by either: - replacing the instructions for the manual change with a link to <https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).…> or a more suitable reference (I could not find a KB article when I looked) - rewording it as, e.g., ... in the registry key HKEY_...FileSystem, set the REG_DWORD value LongPathsEnabled to 1 The value type could be left out; the value is predefined on all platforms where it will be effective. ---------- assignee: docs@python components: Documentation messages: 295505 nosy: Christian.Ullrich, docs@python priority: normal severity: normal status: open title: Unusual Windows registry path syntax type: enhancement versions: Python 3.6 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue30612> _______________________________________

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[issue29986] Documentation recommends raising TypeError from tp_richcompare
by Devin Jeanpierre Oct. 20, 2020

Oct. 20, 2020

New submission from Devin Jeanpierre: am not sure when TypeError is the right choice. Definitely, most of the time I've seen it done, it causes trouble, and NotImplemented usually does something better. For example, see the work in https://bugs.python.org/issue8743 to get set to interoperate correctly with other set-like classes --- a problem caused by the use of TypeError instead of returning NotImplemented (e.g. https://hg.python.org/cpython/rev/3615cdb3b86d). This advice seems to conflict with the usual and expected behavior of objects from Python: e.g. object().__lt__(1) returns NotImplemented rather than raising TypeError, despite < not "making sense" for object. Similarly for file objects and other uncomparable classes. Even complex numbers only return NotImplemented! >>> 1j.__lt__(1j) NotImplemented If this note should be kept, this section could use a decent explanation of the difference between "undefined" (should return NotImplemented) and "nonsensical" (should apparently raise TypeError). Perhaps a reference to an example from the stdlib. ---------- assignee: docs@python components: Documentation messages: 291144 nosy: Devin Jeanpierre, docs@python priority: normal pull_requests: 1167 severity: normal status: open title: Documentation recommends raising TypeError from tp_richcompare _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue29986> _______________________________________

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